According to our experience, vE can be a valuable tool for endoscopic transsphenoidal pituitary surgery for training purposes and preoperative planning. For the novice, it can act as a simulator for endoscopic anatomy and for training surgical tasks. For the experienced pituitary surgeon, vE can depict the individual patient's anatomy, and may, therefore, improve intraoperative orientation. By prospectively visualizing unpredictable anatomical variations, vE may increase the safety of this surgical procedure.

CTA, cognitive task analysisVR, virtual reality.

Endoscopy has recently been introduced to endonasal transsphenoidal pituitary surgery as a minimally invasive procedure for the removal of various kinds of pituitary tumors. To reduce morbidity and mortality with this new technique, the surgeon must be well-trained and well-prepared. Virtual endoscopy can be beneficial as a tool for training, preoperative planning, and intraoperative support. This paper introduces STEPS, a virtual endoscopy system designed to aid surgeons in getting acquainted with the endoscopic view of the anatomy, the handling of instruments, the transsphenoidal approach, and challenges associated with the procedure. STEPS also assists experienced surgeons in planning a real endoscopic intervention by getting familiar with the individual patient anatomy, identifying landmarks, planning the approach, and deciding upon the ideal target position of the actual surgical activity. The application provides interactive visualization, navigation, and perception aids and the possibility of simulating the procedure, including haptic feedback and simulation of surgical instruments.